Xenoturbellida: The fourth deuterostome phylum and the diet of worms

@article{Telford2008XenoturbellidaTF,
  title={Xenoturbellida: The fourth deuterostome phylum and the diet of worms},
  author={Maximilian J. Telford},
  journal={genesis},
  year={2008},
  volume={46}
}
  • M. Telford
  • Published 1 November 2008
  • Biology, Medicine
  • genesis
Since the discovery of the marine worm Xenoturbella bocki in 1915 by Sixten Bock and its first published description by Einar Westblad (Westblad, 1949 , Arkiv Zoologi 1:3–29), Xenoturbella was generally allied to the turbellarian flatworms, perhaps most closely to acoelomorphs. In 1997, however, analyses of ribosomal DNA (Norén and Jondelius, 1997, Nature 390:31–32) and developing oocytes (Israelsson, 1997, Nature 390:32) [and, subsequently, embryos (Israelsson, 1999, Proc R Soc Lond B 266:835… Expand
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Xenacoelomorph-Specific Hox Peptides: Insights into the Phylogeny of Acoels, Nemertodermatids, and Xenoturbellids
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  • Biology, Medicine
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References

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Xenoturbella is a deuterostome that eats molluscs
TLDR
It is shown that the samples in these studies were contaminated by bivalve embryos eaten by Xenoturbella and that XenOTurbella is in fact a deuterostome related to hemichordates and echinoderms. Expand
Feeding ecology of Xenoturbella bocki (phylum Xenoturbellida) revealed by genetic barcoding
TLDR
Xenoturbella only contains molluscan DNA originating from bivalves living in the same environment, refuting former hypotheses of a bivalve relationship and suggesting that Xenoturblla feeds specifically onbivalve prey from multiple species, possibly in the form of eggs and larvae. Expand
New light on the enigmatic Xenoturbella (phylum uncertain): ontogeny and phylogeny
  • O. Israelsson
  • Biology
  • Proceedings of the Royal Society of London. Series B: Biological Sciences
  • 1999
TLDR
The previously unknown embryology of Xenoturbella is reported here that unequivocally corroborates a bivalve relationship and thus once and for all dismisses the potential new phylum plesiomorphic phylum. Expand
Acoel Flatworms Are Not Platyhelminthes: Evidence from Phylogenomics
TLDR
A phylogenomic approach using 68 different protein-coding genes from the acoel Convoluta pulchra and 51 metazoan species belonging to 15 different phyla shows that acoels are not part of the classically defined Platyhelminthes, making the latter polyphyletic. Expand
Nerve cells of Xenoturbella bocki (phylum uncertain) and Harrimania kupfferi (Enteropneusta) are positively immunoreactive to antibodies raised against echinoderm neuropeptides
TLDR
The presence of immunoreactivity against S2 can be interpreted as a synapomorphy of Enteropneusta, Echinodermata, and Xenoturbella spp. Expand
Deuterostome phylogeny reveals monophyletic chordates and the new phylum Xenoturbellida
TLDR
To study the relationships among all deuterostome groups, an alignment of more than 35,000 homologous amino acids is assembled, including new data from a hemichordate, starfish and Xenoturbella and it is concluded that chordates are monophyletic. Expand
The ciliated epidermis of Xenoturbella bocki (Platyhelminthes, Xenoturbellida) with some phylogenetic considerations
TLDR
The epidermis of Xenoturbella bocki Westblad was studied by scanning and transmission electron microscopy and showed a characteristic pattern of axonemal filament termination in the distal tips of their cilia, which may be an apomorphic feature which indicates a close relationship between xenoturbellida, Nemertoder‐matida and Acoela. Expand
The epidermal ciliary rootlets of Xenoturbella bocki (Xenoturbellida) revisited: new support for a possible kinship with the Acoelomorpha (Platyhelminthes)
TLDR
The phylogenetic affinities of Xenoturbella remain highly debateable and a review of recent reports is given, together with a discussion of combinations of current phylogeny hypotheses. Expand
The Nemertodermatida are basal bilaterians and not members of the Platyhelminthes
TLDR
The results imply that the last common ancestor of bilaterian metazoans was a small, benthic, direct developer without segments, coelomic cavities, nephrida or a true brain. Expand
An immunocytochemical and ultrastructural study of the nervous and muscular systems of Xenoturbella westbladi (Bilateria inc. sed.)
TLDR
The results are compatible with the hypothesis of Xenoturbella westbladi forming a sister taxon to Bilateria and the organisation of the nervous system appears very simple. Expand
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